On Sat November 21 2009 1:49:20 pm John Andersen wrote:
On 11/21/2009 9:34 AM, Richard Creighton wrote:
The use of multiple computers each using RAID gives me fault tolerance AND backup with the backup being controlled via a product called CrashPlan, but could be effected via rsync/cron scripts.
I never consider mere copies as backup.
While I applaud you setup for its fault tolerance, a single backup copy is a scenario that has burned me in the past such that I never rely on it any more other than as a disaster cache.
Too often the bone-headed deletion or disastrous program change is faithfully replicated across the synced mirrors before anyone can detect it.
Like yours, my servers and critical workstations are all raid machines.
My synced copies are on similar machines (using Unison ) located is in a different city. Unison is also used by several laptops that need working caches of some sub-trees (principally for software development). <snip>
One advantage I have found to CrashPlan is that it compresses, maintains copies of historical versions <n deep>, copies of erased versions as desired, and copies on multiple machines both locally and remotely which can be restored on demand. The paid version can back up real-time, the free version will back up once every day or upon demand. If your destination is a RAID array which is fault tolerant device, you have pretty good hardware tolerance. Another good feature is that CP periodically checks the stored image(s) to ensure they will reconstruct properly and will notify you if it finds any fault that would prevent it. So no surprises when it is needed down the road. It also notifies you if it is unable to complete a backup for any reason. All in all, the combination of RAID for fault tolerance of large media of my primary system AND my RAID tolerant backups has saved my keester on more than one occasion and fortunately, having more than one backup has so far proven unnecessary redundancy, but IMO, just as soon as I decide to eliminate that redundancy, I will find I needed it, so I don't. Disks are cheap enough now to invest in that as backup. For those that can't afford it, there are services like CrashPlan that offer thousands of Terrabytes of network storage over the internet at reasonable annual rates. I agree with you about tapes. PITA, but better than nothing. -- Richard -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org